Of the 100 billion or more galaxies visible through existing telescopes, most are either spiral or elliptical in shape and about one-fourth are irregular in shape. In addition to their shape, star systems can be further...

Fueled by economic pressure to maximize crop yields and government incentives to produce only one type of crop, contemporary American farmers have been facing a crisis reminiscent of one that hit the Great Plains in the...

Long before the devastating December 2004 Indian Ocean event, tsunamis had already been implicated in the widespread death and destruction in Java and Sumatra following the 1883 eruption of Krakatoa. Tsunamis are also...

This collection of links to lessons, tools and tips is intended for teachers who want to use Google Earth in the classroom. Resources include lesson plans, videos, virtual tours, and other multimedia features. It...

In the early 1900s, most geologists thought that Earth's appearance, including the arrangement of the continents, had changed little since its formation. This video segment describes the impact the theory of plate...